1. Field of the Invention
This invention relates to a plastic container which is suitable for use with a metering element, and to a metering element with a closure for metered dispensing of liquid, free-flowing and pourable media.
2. Description of Related Art
Normally a plastic container represents a storage space and the metering element has a metering chamber. The exit of the medium is effected from the storage space to the outside via the metering chamber.
Such devices often known as metering systems are in varied embodiment forms. While the storage space practically with all solutions is a plastic bottle, the formation of the metering chamber is completely different. In the simplest form the metering chamber is a separate cuplet pushed over the closure which closes the storage space. This solution is simple in manufacture, can be understood and is relatively inexpensive in manufacture. However the handling is problematic. If for example the storage space is relatively large and the cuplet which serves as a metering chamber is small, then material is often spilled. Often the cuplet is not completely filled so that an under-metering takes place.
If the medium to be metered is a washing agent, then the consequences are not particularly relevant, but if it is a medicament, for example a cough syrup, then this is much more unpleasant. A further problem with such metering chambers which are formed as metering cuplets is that after use the dirtied cuplet must first be washed out, otherwise there is a complete dirtying of the closure and of the container.
For these reasons in various systems the metering chamber forms part of a complex closure system. With various movable parts a fixed quantity of a flowable medium first may flow into the chamber. The chamber in an active movement is closed with respect to the storage space, and the metered quantity may flow out of the metering chamber to the outside or may be delivered to the outside. This depends on whether the metering system functions with the piston principle or not. Both are known in various embodiment forms.
Such metering systems are mostly complex and are accordingly expensive, which is why they have only prevailed where the medium to be metered is relatively expensive. Such systems in particular with medicaments are known. Also with the metering of various fine chemicals or adhesives such systems are considered, in particular when an air exchange to the outside is to be avoided.
Finally there are also known metering systems with which the plastic container has a storage space and a connected metering chamber. Such systems are known with fluids, wherein the metering chamber represents a siphon space. The metering is accomplished by allowing fluid flow into the siphon space and afterwards emptying the siphon space. With all these siphon systems the metering is not completely and correctly solved, in particular because in a deformable plastic container, wherein there is an undesired pressure on the plastic container when emptying the metering container, medium may flow from the storage space into the storage space so that an increased dosage is delivered.
Also, when using this system practically only the metering of fluids is possible. The dispensing of free-flowing and pourable media may hardly be realized by way of siphon systems. This is hardly possible with systems with which the metering is effected by way of piston cylinder units. It is one object of this invention to provide a plastic container particularly suitable for use with metering elements or other means which demand an active movement of means relative to the storage space of the plastic container.
This object is achieved by a plastic container described in this specification and in the claims. Because of possible axial relative movement, according to this invention, of the container edge to the storage space of the plastic container, there is a movement component which considerably simplifies the formation of an active movement element, such as a pump or metering element.
It is a further object of this invention to provide a metering element which provides an inexpensive and simply manufacturable metering system which is suitable for liquid as well as free-flowing or pourable media.
This object is achieved with a metering element with a closure, which is particularly simple since it does not have any active-moving elements. The active movement is assumed for example by a plastic container. Unusually for the metering capability, the closure is actively involved in the functioning.
Further advantageous embodiment forms of this invention are deduced from the dependent claims and are explained in the subsequent description with regard to the functioning and significance.